C56 gearbox fit AE92 Bigport Redtop

[Crampy]

Hi all.
Just been browsing around and see Warwick (Mr Revhead) recommended a C56 from a S/S AE111 as a good upgrade for an AE92, due to the better ratios and having a factory LSD.

Is it a straight swap with the C52, or does it need a few other things to work? From my understanding, the clutch on the Bigport Redtop is the same size as the 20 Valve ones (~215mm), so that would work. Is the input spline the same between the two? Will the drive shafts go straight in, or will I need 20 Valve jobbies?

Also, does anyone know where I could buy one and what they're worth?

Cheers for any help.

[gmacrae]

Your bigport clutch is 200mm i think, where 20v is about 214mm. Your current clutch will fit the c56 box fine, though i'd replace the clutch while your in there - may as well use a 20v flywheel and clutch (pm me if you want a silvertop flywheel).

The c56 uses a different drivers side driveshaft setup, its extended and braced on a hanger on the block so inner cv is close to the outer cv like passenger side... Not sure if you'll be able to use your current driveshafts in the c56 or not? I'd grab 20v ones if you can.

[AceSniper]

your stock shafts will go into the c56, just because a car is s/s it may not be lsd, You will need to swap the speedo drives over... easy

[Crampy]

Sweet, cheers AceSniper.
I had a S/S AE111 BZ-G and I was sure it didn't have an LSD, so cheers for the insight.


I'm pretty sure the Bigport Redtop has a 214mm clutch as well. The Bluetop has the 200mm one.

I was going to use a Blacktop 20 Valve Flywheel and hence a 20 Valve clutch kit anyway. So it doesn't really matter:)